tools/version.sh: Use backup files on Win32

Windows doesn't permit us to edit a file in-place with Perl.
So create backup files when we perform the edit, and remove them
when we are done.  This is a tad slower on POSIX systems, but is
much more portable.

Change-Id: I429c7d698924cb32e709363f5da82f7232bbdab2
Signed-off-by: Shawn O. Pearce <spearce@spearce.org>
1 file changed